A DISCRETE HUBBARD-STRATONOVICH DECOMPOSITION FOR GENERAL, FERMIONIC 2-BODY INTERACTIONS

A scheme is presented to decompose the exponential of a two-body opera tor in a discrete sum over exponentials of one-body operators. This di screte decomposition can be used instead of the Hubbard-Stratonovich t ransformation in auxiliary-field quantum Monte Carlo methods. As an il lustration, the decomposition is applied to the Hubbard model, where i t is equivalent to the discrete Hubbard-Stratonovich transformation in troduced by Hirsch, and to the nuclear pairing Hamiltonian. (C) 1998 E lsevier Science B.V.